Indirect Radiators

New England SteamWorks

We've come across a grand old home with indirect heating. Unfortunately, a bunch of the indirect radiators towards the front of the home were removed long ago from their basement ceiling location. And naturally, the front of the home does not heat very well. Due to the layout of the rooms and the architecture, installing radiators in the rooms themselves is not a good option. The best option would be to reinstall some indirects in the basement.

Setting aside the logistics of installation for the time being, the first order of business would be sourcing them. They are, of course, enormous. I haven't done any calculations yet, but based on their cousins hanging in the basement, we're talking a minimum of 200 EDR. Perhaps 300.

The only thing I've been able to come up with are these cast iron convectors:



But the largest only has an EDR of 55. I called the manufacturer about some custom work, but they were no help at all.

Anyone with any experience here, or ideas?

JUGHNE

While knocking apart the sections of a smallish CI boiler, I got to thinking that this bare unit would make quite a radiator.

I suppose buying just end sections and one or two boiler sections would be cost prohibitive to consider to construct a pin radiator?

EBEBRATT-Ed

Not an elegant fix but an air handler with a steam coil would work.

mattmia2

What about getting some salvaged sections of that utility type cast iron radiator they hang on the walls of gyms and warehouses and such or is even stacking a couple sections of that nowhere near the EDR you need? Obviously the pins on the original indirect radiators gave them a very dense amount of surface area.

mattmia2

EBEBRATT-Ed said:

Not an elegant fix but an air handler with a steam coil would work.

Or hot water coils off the water in the boiler.

New England SteamWorks

JUGHNE said:

While knocking apart the sections of a smallish CI boiler, I got to thinking that this bare unit would make quite a radiator.

I suppose buying just end sections and one or two boiler sections would be cost prohibitive to consider to construct a pin radiator?

This was my first idea, but no one sells just sections for residential boilers. They are all packaged now. Commercial sections likely too unwieldy to get up and installed.

New England SteamWorks

mattmia2 said:

EBEBRATT-Ed said:

Not an elegant fix but an air handler with a steam coil would work.

Or hot water coils off the water in the boiler.

The boiler is quite a distance from where the indirect radiators are needed, and using hot water with its reduction in heat output wouldn't seem to make a lot of sense, considering the BTUs needed for this application. Plus steam is already available at the location.

leonz

That is a real shame, would a mule train(multiples) of cast panel radiators piped in series be a good substitute for the radiators that were removed?

The Hudson Reed folks in England make and hand assemble very tall thin 3 tube radiators.

Governale in Queens, NY and OCS in Brooklyn, NY make convector radiators- if you have already looked at them I am covering old ground I guess,

EBEBRATT-Ed

Spirotherm makes "Speed Heat" high output fin tube. It's copper though and I don't see any steam rating on it but don't see why it couldn't be used. You could call them. See attached.

Beacon Morris makes 1 1/4 & 2" steel fin tube with a steam rating. maybe a better choice.

See attached

DanHolohan

How about fintube baseboard in rows, top to bottom. Set it up like shoelaces, back and forth. Feed the top and vent (or trap) the bottom.

New England SteamWorks

That's a promising idea. Also much lighter weight than trying to hang some huge cast iron in the ceiling. The only worry I guess would be the imbalance of heat retention, with the rest of the house being all cast iron. But there isn't going to be a perfect solution here....

mattmia2

Even a little bit of forced convection would greatly increase the effective EDR you can get from a given emitter surface area(although it also would reduce the time that the mass continued to emit heat).

I suggested hot water coils because you have a lot more flexibility in how they are oriented and you can zone them separately.

New England SteamWorks

This indirect system is all convection baby!

gerry gill

Have you called Burnham and asked if you can buy some Independence boilers' blocks?

New England SteamWorks

gerry gill said:

Have you called Burnham and asked if you can buy some Independence boilers' blocks?

Yes. No go. Warranty claims only.

JoeEngineer

Going outside the box, has adding blown in cellulose or foam to reduce the heating load been considered? If it is as grand and old as you suggest you might be able to cut the need to a small fraction of that originally required; increase comfort, reduce heating costs tremendously and, most importantly fit what you need back into the space or possibly. Also, this grand old home may have been fitted with enough capacity to heat it with the windows open; has a heating load been done?

New England SteamWorks

There's more than enough capacity, original boiler still there. There's just no heat emitters in the front of the house. These type of systems didn't need windows open. Cold outside air was ducted in...

https://heatinghelp.com/systems-help-center/indirect-heating-systems/

jessestaton

As JoeEngineer said, the replacement units probably do not need to be as large as the originals if the home is tighter than when it was built.
I see a company called Runtal has a product called Steam Flow Form for Two Pipe systems. Supposed to be mounted to the floor but maybe they could build it with the inlet/outlets upside down.
Or just wall/ceiling units? Possibly fabricate a hanging system so they could be stacked?

New England SteamWorks

They don't need to be as large as the originals, but they still need to be very large. They have to heat 3 floors.

EdTheHeaterMan

With a different heat emitter than the originals in the rear of the home, How do you plan on controlling the heat output? Originally a hand fired system would not have had a thermostat, just valves on the individual radiators to shut off sections that were overheating. With anything that is not designed as the Dead Men intended, you will always have a temperature imbalance unless you have some way to control the output from the different emitters.

Have you considered a buffer tank or some other way to store hot water, or perhaps a separate heating system completely, operated by a thermostat in the front of the home. You could design based on 180°F input using any type of fin coil inserted in the openings where the old indirect cast iron units were located. There are several companies that will build custom coils to fit specific spaces.

https://usacoil.com/hot-water-coil/

You would probably want freeze protection or antifreeze in those coils, since very cold outdoor air will be in contact with them, if installed to as the old steamer were.

Nick_Castrads

I know a couple of foundries still making cast iron boiler sections like this. Would that help you? The connector nipples are - I think - 2" conical. No idea what the EDR is but I could probably find out.

New England SteamWorks

Yes, Nick, that would be terrific. Loved your NYC presentation, BTW!

Nick_Castrads

Thanks Ryan! Any idea how many sections you'd need and in what size of grouping?

New England SteamWorks

No, not yet. That's phase II. Phase one is identifying what to use. So if you could just check that they will sell sections, that will be enough for now.

JoeEngineer

If this grand old house was uninsulated and fitted with "leaky" old windows the easiest solution might be to thoroughly insulate and weatherstrip (or possibly even change out for insulated low E) windows; this would:
A.) Greatly reduce your infiltration losses.
B.) Greatly reduce your transmission losses.
C.) Greatly reduce your radiation losses.
Your heating load will be cut by more than half; take half of the remaining indirect from the rear of the house and use it to heat the front, replace your old (presumably oil) steam boiler with a modern high efficiency steam boiler of half the size. I would be willing to wager these improvements will make for a much more comfortable (less drafty) house indwell pay for themselves in a matter of years

Charlie from wmass

What @EBEBRATT-Ed said. You can price out hanging the same edr in wall hung radiators. The air handler will be better. 

ricka1234

what about running radiant or baseboard? using a superstor off steam boiler

Nick_Castrads

@New England SteamWorks - spoke to the foundry, they're happy to sell the sections. Email me with details? 

jpm659er

Is the system really still setup to draw in and heat outside air? Who still does that? With Mattmia2’s idea of an air handler setup, you can recirculate the air. Seems like you would need a fraction of the original EDR as well.

jim s_2

Why were the original indirects removed in the first place??

mikespipe

You could create a manifold and tie a number of the cast iron convectors together. We sell some used ones that are bigger than what's available now , But even new ones combined should be able to give you what you need. And you probably don't need as much as you think due to improvements in windows and insulation. I don't think boiler sections will work as they are designed to take very hot temps to heat interior water not to radiate lower temp. I also recommend that the new radiator be on a separate zone , that would give you better control and let it heat properly even if either undersized or oversized.

mikespipe

also if you use a air handler , that is on a separate zone, you should be able to provide the heat needed, insulate the house if it has not been done already and you will greatly reduce the btu's needed.